


Case Closed

by lollipop1141



Series: Dabble in Drabbles [13]
Category: Miraculous Ladybug, 名探偵コナン | Detective Conan | Case Closed
Genre: Adrien is an anime weeb, Conan doesn't believe in magic, Conan gives everyone a heart attack, F/M, Gen, Identity Reveal, Unconventional lucky charm, You ain't slick Adrien
Language: English
Status: Completed
Published: 2020-10-13
Updated: 2020-10-13
Packaged: 2021-03-07 23:02:42
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,252
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26995597
Author URL: https://archiveofourown.org/users/lollipop1141/pseuds/lollipop1141
Summary: "Whatever remains, however improbable, must be the truth."In which Adrien is reminded not to underestimate kids - especially a 7 year old Japanese kid who seems too smart for his own age
Relationships: Adrien Agreste | Chat Noir & Marinette Dupain-Cheng | Ladybug, Adrien Agreste | Chat Noir &; Kudou Shinichi | Edogawa Conan, Kudou Shinichi | Edogawa Conan & Mouri Ran
Series: Dabble in Drabbles [13]
Series URL: https://archiveofourown.org/series/1759576
Comments: 17
Kudos: 84





	Case Closed

**Author's Note:**

> We need more ladybug/detective conan crossovers. Just for the sake of Conan not believing that magic is real until it hits him in the face lmao
> 
> Detective Conan: a seventeen year old detective, Kudou Shinichi, witnesses an illegal transaction and suffered the consequences by being forced to take a pill that shrunk him back into his 7 year old body.
> 
> Miraculous Ladybug: Marinette and Adrien are ordinary students by day, and the respective Ladybug and Chat Noir superheroes by night (or whenever there is an akuma villain attack). 
> 
> Anyway,
> 
> Nee-chan = big sister (even though they're not related)
> 
> Nii-san = big brother (even though they're not related)

Adrien was taking a stroll through a park, when he bumped into a small child, sending him sprawling on the ground.

"I'm so sorry! Kid, are you alright?" Adrien said frantically as he helped the child up and gave him back his glasses. The kid nodded in thanks as he put it on. He looked about 7 years old, wearing a blue shirt, blue shorts, red shoes, and a red bow tie around his neck. "What's your name?"

The kid said something in Japanese. Adrien frowned. "Conan? Like Arthur Conan Doyle?"

The boy, Conan, looked surprised. "You can understand Japanese?!"

Adrien grinned. "Well, I didn't watch all that anime for nothing."

Conan laughed and Adrien joined in. Standing up, Adrien held out his hand and said, "So, Conan, are you lost?"

Conan nodded as he took his hand. "I was in a tour group with my guardian, Ran nee-chan, but I got separated."

"Well then, let's go find her, shall we?" Adrien said with a smile. "Oh, and I'm Adrien."

"Adrien nii-san." Conan rolled the name around his tongue. Adrien was thrilled with being called a 'nii-san' by an actual Japanese person.

As they searched for the kid's guardian, Adrien learned several things about Japan. First, that Japanese people don't really like 'otaku' (Sad, but true). Anime was a big part of the culture there, and you eat sushi in one bite.

Suddenly, screams pierced the air. Adrien stiffened. He sensed an akuma attack. What surprised him more, however, was Conan running towards the source of the screams. "Wait, Conan! Come back! It's too dangerous!"

The boy didn't seem to hear. Fear gripped his heart. If the kid got hurt, he would never forgive himself. He ran after him, praying that nothing bad would happen.

They arrived at the square where a man with manga papers for skin, stood at the top of the fountain, bellowing, "I AM ANIMA! FEAR ME!"

Peeling off his skin, he sliced it towards fleeing people, turning them into comic icons trapped in manga panels.

Conan stood there, flabbergasted. "W-What is that?!"

Anima spotted him. Before Conan could get hit, Adrien grabbed the boy and they barreled into an abandoned shop.

The boy was still in a dazed state and Adrien couldn't blame him. This must have been his first time seeing an akuma attack. Peeking through the window, he breathed a sigh of relief as he spotted a red blur swinging in the rooftops.

"Conan, I want you to stay here. Ladybug will take care of everything." Adrien said gently to the boy.

He looked at the young model with wide eyes. "T-That thing-"

"It's a long story." Adrien said. "I'm going to go out there and search for help. Stay here. You'll be safe. Everything will end soon, I promise."

And with that, Adrien dashed out of the shop and into an abandoned alley, transforming into his alter ego.

* * *

"Good afternoon, my lady." Chat Noir said smoothly, landing in all fours beside her. "Looks like things are a bit _animated_ right now."

"Chat, focus." Ladybug snapped. This akuma was tougher than the previous ones that they had encountered. If they got too near, Anima would turn them into fictional characters and put them in a comic panel (oh the irony).

After a few minutes of fruitless efforts, Ladybug deemed it time to use her last resort. She threw her yo-yo in the air.

LUCKY CHARM

And out fell a skateboard.

"What am I going to do with this?!" Ladybug screeched. "I don't know how to skate!"

Suddenly, Conan, who had spotted the skateboard, dashed out of the shop. Grabbing the contraption from her arms, he said, "I'm borrowing this!"

And with that, he ran towards the akuma.

"Wait, what?!" Ladybug blinked. "Kid! Come back here!"

"Conan! Come back!" Chat Noir cried out.

Conan faltered for a fraction of a second, but continued to run. He saw a ramp-like structure and began to skate towards it. As he and the skateboard flipped in the air, like slow motion, Conan directed his wristwatch to the direction of the akuma and pressed a button. A small dart flew through the air and pierced the neck of Anima.

The akuma staggered around and then fell on the ground with a thud. The skateboard clattered and swiftly drifted to a stop. Conan flipped it up and tucked it under his arm as he headed towards the akuma with a rattled, yet triumphant smirk on his lips.

Unclasping the necklace from around Anima's neck, Conan headed towards the two shocked superheroes. He handed the necklace to Ladybug saying, "Here."

Ladybug blinked, wondering what he just said. Chat Noir said, "Finish the job, my lady."

A few seconds later, everything returned to normal. Conan gazed around a repaired Paris in amazement. He looked up at them. With a grin, he said in French, " _Affaire classée._ "

The two teenagers would've just stood there, gawking at him, if it weren't for their miraculous beeping in warning. With half-assed excuses, Chat Noir and Ladybug ran in opposite directions.

Conan looked at the two in confusion. With a shrug, he searched for a bench to sit on and wait for Adrien.

* * *

Adrien arrived, panting. "S-sorry about that, Conan. I was held up and-"

"So the black and red lady doesn't know you're Kuro Neko?" Conan asked innocently.

**What?**

"W-what are you talking about, Conan?" Adrien asked nervously.

" _Whatever remains, however improbable, must be the truth_." Conan said. And at that moment, there was something ominous about the child. He tapped his temple. "You left, Kuro Neko appeared, and vice versa. You have the same eyes, voice, hair, etc. It's elementary."

Adrien gulped. The observation skills of this kid was frightening. For a second there, Conan was like a different person entirely.

"It's Chat Noir, actually." Adrien corrected. "And-"

"Don't worry." Conan chirped. The innocent child was back. "I won't tell anyone."

Adrien sighed in relief.

"Conan-kun!"

Adrien and Conan looked up, spotting a 17 year old Japanese girl rushing towards them with Marinette trailing behind her.

"Ran nee-chan!" Conan brightened up. Ran sank down to her knees and wrapped the boy into a bone-crushing hug. He squeaked, his face turning red.

"You had me so worried!" Ran cried. Conan's eyes widened and then grew soft as he gazed at her.

Conan said quietly, "Sorry."

Adrien and Marinette stood a few feet away. The moment felt too intimate to interrupt; which was ridiculous, since the girl was 17 and Conan was just an elementary kid. Or was he really?

Adrien gave a smile to his classmate. "So you helped her?"

"I d-dud- I mean, I did." Marinette stuttered, her face steaming.

Standing up, Ran bowed to them and said in clumsy French, "Thank you very much!"

"It's no problem." Adrien said easily in Japanese. Marinette and Ran stared at him in shock.

Conan piped up, "He learned from binge-watching anime."

Adrien frowned. 'Binge-watching' was an unnecessary comment. Conan just smiled cheekily at him.

"O-Oh. Well then," Ran smiled pleasantly at the two. "Thank you both so much. Conan-kun must've been a handful."

Conan grouched. "Not that much."

She raised an eyebrow. Conan hung his head in guilt. It seemed like this had already happened a few times. Taking one last bow, she said to the kid, "Conan-kun, let's go."

As he watched them leave, Adrien muttered under his breath, "Conan, who are you?"

Conan looked over his shoulder, met his eyes, and smirked.

"Edogawa Conan. A detective."

**Author's Note:**

> I was having Detective Conan nostalgia so I clashed two of my favorite fandoms together. If you haven't watched Detective Conan/Case Closed, I definitely recommend it! It's awesome!
> 
> Of course, this can be read without having to know about Detective Conan. Also, Kuro Neko means Black Cat in Japanese.
> 
> But I wrote this because I was feeling lonely. Am I the only one who's into Detective Conan while being in MLB as well?
> 
> Anyway, see ya'll next time!


End file.
